Spontaneous
Bacterial Peritonitis
Katherine Yu
May 2014
Objectives
• Know how to diagnose spontaneous bacterial peritonitis (SBP)
• Know how to treat SBP
• Know the indications for the primary prophylaxis of SBP and
the treatment regimen
Case
• A 45 year old man is admitted to the hospital for a two day history of
fever and abdominal pain. His medical history is notable for cirrhosis
due to chronic hepatitis C, esophageal varices, ascites, and minimal
hepatic encephalopathy.
• On physical exam, T 36.5C, BP 100/50, P 84, RR 20. BMI 28.
Abdominal exam discloses distension consistent with ascites.
• Labs: WBC 3.5, Hgb 10, Plt 70. Cr 1.8. Total bilirubin 4. ALT 30, AST
40. Diagnostic paracentesis discloses a cell count of 2,000/microliter
with 20% neutrophils, a total protein level 1 g/dL, and an albumin of
0.7 g/dL. Ascitic fluid culture is positive.
• What is his diagnosis?
• What is the most appropriate treatment?
Diagnosis
• SBP is diagnosed by an ascites cell count of ≥ 250 PMNs/mm3
and a positive ascitic fluid culture
• How to calculate the number of PMNs in ascitic fluid:
• Ascitic fluid cell count multiplied by the percentage of PMNs
• Example:
• Ascitic fluid cell count is 1,000 and there are 30% PMNs
• The number of PMNs is 1,000 x 0.3 = 300
Diagnosis
Type
Ascites cell
count/mm3
Ascites culture
Spontaneous bacterial
peritonitis (SBP)
≥ 250 PMNs
Usually polymicrobial.
Microbiology: 70% GNR (E.
coli, Klebsiella), 30% GPC
(enterococcus, S. pneumo).
Less commonly nosocomial
(fungi, pseudomonas)
• Be aware there is also culture negative neutrocytic ascites (CNNA) with ≥
250 PMNs/mm3 but with negative ascites culture.
Treatment
• Cefotaxime 2 gm IV q8 hours for 5 days
• Oral fluoroquinolone can be used for uncomplicated SBP
(stable renal and hepatic function and no encephalopathy)
• The addition of IV albumin 1.5 g/kg at the time of diagnosis
and 1 g/kg on day three may increase survival and reduce the
rate of renal impairment when compared with antibiotics
alone
• If patient is not improving, consider repeat paracentesis at 48
hours
Indications for Prophylaxis
• Primary prophylaxis:
• If ascitic fluid total protein (AFTP) < 1.5 & Na <130, Cr >1.2 or
Child-Pugh score B
• Secondary prophylaxis:
• If prior history of SBP
• Regimen:
• norfloxacin 400 mg po daily -OR • Bactrim DS daily
• Benefits of prophylaxis:
• Improves 1 year survival probability
• Reduces 1 year probability of SBP
Back to the case
• A 45 year old man is admitted to the hospital for a two day history of
fever and abdominal pain. His medical history is notable for cirrhosis
due to chronic hepatitis C, esophageal varices, ascites, and minimal
hepatic encephalopathy.
• On physical exam, T 36.5C, BP 100/50, P 84, RR 20. BMI 28.
Abdominal exam discloses distension consistent with ascites.
• Labs: WBC 3.5, Hgb 10, Plt 70. Cr 1.8. Total bilirubin 4. ALT 30, AST
40. Diagnostic paracentesis discloses a cell count of 2,000/microliter
with 20% neutrophils, a total protein level 1 g/dL, and an albumin of
0.7 g/dL. Ascitic fluid culture is positive.
• What is his diagnosis?
• What is the most appropriate treatment?
Summary
• Spontaneous bacterial peritonitis (SBP) is diagnosed by an
ascites fluid cell count of ≥ 250 PMNs and a positive ascites
fluid culture.
• Treatment of SBP is IV cefotaxime 2 gm IV q8 hours and IV
albumin 1.5 g/kg on day one and 1 g/kg on day 3. The
concomitant use of albumin with antibiotic therapy is
associated with a survival benefit compared with antibiotic
therapy alone.
• Primary prophylaxis of SBP is indicated if ascitic fluid total
protein (AFTP) < 1.5 & Na <130, Cr >1.2 or Child-Pugh score B.
The treatment is daily oral norfloxacin or Bactrim DS.